The probability of having liver or thyroid function
alteration or autoAb occurrence was analyzed longitudinally with the generalized
estimating equations (GEE) approach.

At baseline, 16.1% of patients had
autoAb.

During treatment, autoAb occurred de novo in 7.2% of patients.
GEE analysis showed that the probability of having autoAb at any time during
IFN-beta1b treatment did not change significantly compared with baseline.
AutoAb occurring de novo rarely persisted during treatment and significantly
less than those already present at baseline.

Positivity for autoAb at baseline
or during treatment was not correlated with the development of thyroid
or liver function alteration during IFN-beta1b treatment.

Our study indicates
that IFN-beta treatment is a safe treatment for MS patients, free of risk
of autoimmunity and of associated liver or thyroid function alteration.